Crocodile clamp

What is a crocodile clamp?

A crocodile clamp (also called a crocodile clip, and in American English an alligator clip) is a spring clip with a long, saw-toothed jaw, made to make temporary electrical contact with a bare wire or a battery terminal. The name comes from the resemblance of the jaw and teeth to those of a crocodile. In BDSM it ends up on nipples or skin folds, well outside anything it was designed for.

Where the name and the thing come from

From telephony, and it is one of the few toys with a name written into a defense standard.

The year is 1906. John H. Williams of the Cuyahoga Telephone Company showed his find to the founder of Mueller Electric: a wire with a lamp in the middle and one of these clips at each end, so a lineman could tap onto a live wire for a moment. Harry Frankel of New York had patented something similar back in 1903, and Westinghouse engineer George Brown Dusinberre filed the design it eventually became in 1909. The English encyclopedia lines the three of them up side by side.

Two names, two lines in a standard. The American Defense Logistics Agency separates them in Commercial Item Description A-A-59466 as distinct types: a crocodile clip is type CC, and an alligator clip falls under the TCx series. Mueller Electric itself still calls itself the inventor and has been in the trade since 1908. In their 1922 Cleveland factory, now a listed historic building, forty-eight women assembled up to eighty-five thousand clips a day.

Why people reach for this clip in particular

Because it is lying around. A crocodile clamp costs a couple of euros at the electronics store, sits in every toolbox, and asks for no decision at all: you squeeze and it holds. For the person putting it on, that is the appeal, and for the person receiving it the effect sits in that same bluntness. There is nothing to adjust, so the question is not how hard but where and how long.

That is also its limit. A clip out of a toolbox was never drawn with a body in mind, and you feel that in the teeth.

What to watch for with a crocodile clamp

Three things, all of them tied to where it came from.

The plastic sleeve you see around it is there against short circuits, not against skin. Under that sleeve sits the same bare, stamped jaw. The encyclopedia also notes what the metal is: the first models were steel with zinc, and because zinc fouled quickly Mueller switched to nickel plating. Nickel that lies against the skin for a long stretch is exactly what the European limit is about, and that is laid out at chain.

And this thing conducts. That is what it exists for. Hook anything electrical to it and the rules of elektroplay apply, not those of a nipple clamp. How long a toothed clip may stay on is covered at alligator clamp.

Where this fits on this site

Pain play in three settings is on my yes-list, and so is nipple play. The BDSM date explains how an evening like that gets arranged beforehand.

Sources

• Crocodile clip. Wikipedia (the article has carried a maintenance banner about its number of citations since May 2013; the points used here are the ones that are actually referenced). Provides the description as a plier-like, spring-loaded metal clip with a long toothed jaw for temporary electrical contact, the origin of the name in the resemblance to the jaw of a crocodile or alligator, the length of 15 to 40 millimeters for laboratory versions, the plastic sleeve or “boot” meant to prevent short circuits, the introduction by John H. Williams in 1906 to the founder of Mueller Electric as a wire with a lamp and a clip at each end, Harry Frankel of New York’s 1903 patent and Westinghouse engineer George Brown Dusinberre’s 1909 patent, the first models of steel with zinc that fouled quickly before the switch to nickel plating, and Commercial Item Description A-A-59466 of the American Defense Logistics Agency, in which crocodile clips are type CC and alligator clips fall under the TCx types.
• Krokodillenklem. Wikipedia (Dutch). Provides the Dutch names crocodile jaw, grip clip and spring clip, the comparison with a clothespin for the two tapering parts pressed together by a spring, the use on a bare lead, a pin or a battery terminal, and the name battery clamp for the heavy battery version.
• The Inventor of the Alligator Clip. Mueller Electric Company, accessed 2026. The manufacturer itself, and so the party with authority over its own production history. Provides the claim to be the inventor of the alligator clip, the year 1908 as its start, and the 1922 Cleveland factory that is on the National Register of Historic Places, where forty-eight women assembled up to eighty-five thousand clips a day.

Related terms

• Alligator clamp. The same clip under the American name, with the time limit and what taking it off does.
• Clamps. The tool type the crocodile clamp falls under, with the four model families side by side.
• Clothespins. The counterpart without teeth, where you dose with the number of them instead of with force.
• Elektroplay. What applies the moment you use a clip for what it was meant for: current.
• Chain. The other piece of metal on this list, and where the nickel limit is explained.
• Nipple clamps. The use this clip is borrowed for most often, and why taking it off is the hardest part.
• Wasknijpers. The clothespin this type gets compared to, with the spring as its only specification.